The invention relates to a hinge for hanging a flush door on a cabinet carcase in which the size of the door opening is defined by the cabinet facing, the door when closed being set within the facing. Such a hinge has a four-joint mechanism whose pivot axis shifts in space and whose links are pivoted at their door-related extremities in a cup set in a recess in the back of the door, and at their carcase-related extremities on a door-supporting arm adjustably mounted on a mounting plate fastened to the inner surface of the facing; the supporting arm projects toward the door opening beyond the edge of the cabinet facing, and its cantilevered front end section is bent approximately at right angles to the door and, when the door is closed, enters the interior of the cup.
The known hinge of this kind (DE-OS No. 24 58 294) has proven practical for the special application for which it was intended, namely the hanging of a door on a cabinet carcase in which the size of the door opening is defined by the cabinet casing, and for that reason it is used to a considerable extent on such cabinets. The manner in which the supporting arm is adjustably fastened on the mounting plate (which is fastened to the back of the facing) is the same as in the case of the normal hanging of doors by means of hinges provided on the carcase side wall, i.e., after loosening a screw driven through a slot in the back of the door-supporting arm into a tap in the mounting plate, the supporting arm can be shifted relative to the mounting plate to the degree permitted by the length of the slot, and can be locked in place again at selected positions along the slot by tightening the screw. The longitudinal adjustment of the supporting arm of such hinges, however, is a rather difficult task, because it is possible that a correct setting or one that needs to be corrected but slightly will immediately be lost when the screw is loosened, since the weight of the door acts on the front end of the supporting arm and seeks to shift it out of place. In ordinary cabinets, i.e., cabinets without any facing, the supporting wall is easy to reach when the door is open, so that any unintentional shifting of the hinge when the screw is loosened can be prevented by pressing the supporting arm against the mounting plate. Owing to the greater difficulty involved in reaching the supporting arm (and mounting plate) on the back of the cabinet facing, such adjustment of the known hinge is more difficult, and as a rule requires the aid of a second person to support the door while the adjustment is being made.
The invention is addressed to the problem of improving the known hinges when they are intended for the special application described above, such that, in addition to being able to be installed and removed with the same simplicity and speed, they will be precisely and accurately adjustable without difficulty, while any undesired and unintended shifting will be impossible.